@article {47465,
	title = {Ensemble cryo-EM uncovers inchworm-like translocation of a viral IRES through the ribosome.},
	journal = {eLife},
	volume = {5},
	year = {2016},
	month = {2016 May 9},
	abstract = {<p>Internal ribosome entry sites (IRESs) mediate cap-independent translation of viral mRNAs. Using electron cryo-microscopy of a single specimen, we present five ribosome structures formed with the Taura syndrome virus IRES and translocase eEF2{\textbullet}GTP bound with sordarin. The structures suggest a trajectory of IRES translocation, required for translation initiation, and provide an unprecedented view of eEF2 dynamics. The IRES rearranges from extended to bent to extended conformations. This inchworm-like movement is coupled with ribosomal inter-subunit rotation and 40S head swivel. eEF2, attached to the 60S subunit, slides along the rotating 40S subunit to enter the A site. Its diphthamide-bearing tip at domain IV separates the tRNA-mRNA-like pseudoknot I (PKI) of the IRES from the decoding center. This unlocks 40S domains, facilitating head swivel and biasing IRES translocation via hitherto-elusive intermediates with PKI captured between the A and P sites. The structures suggest missing links in our understanding of tRNA translocation.</p>
},
	issn = {2050-084X},
	doi = {10.7554/eLife.14874},
	author = {Abeyrathne, Priyanka D and Koh, Cha San and Grant, Timothy and Grigorieff, Nikolaus and Korostelev, Andrei A}
}
